(METH)ACRYLIC ACID PRODUCTION METHOD, AND, HYDROPHILIC RESIN PRODUCTION METHOD

摘要

The present invention provides a method for producing (meth)acrylic acid, which achieves enhanced productivity or a reduced amount of a catalyst in production of (meth)acrylic acid from 3-hydroxycarboxylic acid, and enables stable production of (meth)acrylic acid at low cost. The method is a method for producing (meth)acrylic acid using 3-hydroxycarboxylic acid as a starting material, the method including a polymerization step of polymerizing 3-hydroxycarboxylic acid to generate a composition containing a 3-hydroxycarboxylic acid polymer, and a step of generating (meth)acrylic acid from the composition containing the 3-hydroxycarboxylic acid polymer, the 3-hydroxycarboxylic acid polymer obtained in the polymerization step including trimer or higher order units, the trimer or higher order units constituting 3% by mass or more of a total of 100% by mass of the 3-hydroxycarboxylic acid and the 3-hydroxycarboxylic acid polymer.